Foam generating attachment for fog nozzles



June 5, 1951 m, UTLER 2,555,394

FOAM GENERATING ATTACHMENT FOR FOG NOZZLE-5'5 Filed April 21, 1950 Patented June 5, 1951 FOAM GENERATING ATTACHMENT FOR FOG NOZZLES Daniel M. Butler, Houston, Tex.

Application April 21, 1950, Serial No. 157,380

8 Claims. (01. 169-15) The invention relates to fire fighting equipment, and concerns more particularly a foam generating attachment for use in conjunction with a conventional fog nozzle.

In the use of water as a fire fighting medium it is common practice to disperse the water to form a fine mist or spray, usually referred to as fog. In this highly dispersed form the Water covers more surface and is more effective as a blanket for smothering the fire. Equipment required for producing fog is relatively simple, comprising merely a suitable nozzle for attachment to the discharge end of a fire hose. These nozzles are of different types, some of them effecting a dispersion by impingement of water streams against each other and others accomplishing the desired result by impingement of water streams against metal surfaces.

It is also common practice, particularly when fighting large fires, to use as a fire fighting medium a relatively stable foam comprising a dispersion of water and air containing, in addition, a suitable foam producing liquid. In generating foam the water and foam producing liquid are usually mixed in suitable proportions, and thereafter the liquid mixture is dispersed in air to form finely divided particles of foam. Various proportioning devices have been used for mixing water and foam producing liquids, injectors of the Venturi type sometimes being used for this purpose. Foam generating nozzles of different types, suitable for attachment to the discharge end of a fire hose, have been developed for use in dispersing the liquid mixture in air to produce foam.

It is an object of the invention to provide an attachment for a conventional fog nozzle which will enable the fog nozzle to be used to generate foam as well as fog, thus increasing the utility of the fog nozzle as well as providing a simple, inexpensive and effective device for generating foam.

It is a further object of the invention to provide a foam generating device which is capable of generating comparatively large volumes of foam for a given size line and pump pressure, all other conditions being comparable.

Another object of the invention is to provide a foam generating device which is capable of generating comparatively large volumes of foam without any sacrifice in the distance which the foam so generated may be thrown, upon being discharged from the device, by action of the pressure in the line.

The invention will be readily understood by referring to the following description and the accompanying drawing, in which:

Fig. l is a view, partly in section, showing a foam generating device embodying the invention.

Fig. 2 is a sectional view taken on the line 2-2 of Fig. 1.

Fig. 3 is an end view taken on the line 33 of Fig. 1.

Referring to the drawing, the numeral I indicates generally a conventional fog nozzle and the numeral 2 indicates generally an attachment which, in combination with the fog nozzle, forms a foam generating device embodying the invention.

The nozzle I includes a pair of concentric tubular members 3 and 4. The tubular member 3 has a female end which is internally threaded to receive one end of a fire hose and a male end which is externally threaded and is disposed within the tubular member 4. One end of the tubular member 4 is internally threaded to receive the tubular member 3, and the opposite end of the tubular member 4 forms the discharge end of the nozzle I.

An orifice 5 is formed in the discharge end of the nozzle I, and a valve seat 6 is provided on the discharge side of the orifice 5. A valve disc I is secured to one end of a valve stem 8 which extends thru the orifice 5 and is disposed concentrically with respect to the tubular member 3. The valve stem 8 is secured to a spider 9 which in turn is secured to the inner wall of the tubular member 3. The arrangement is such that when the tubular members 3- and 4 are rotated with respect to each other the valve disc 1 is advanced and retracted with respect to the valve seat 6.

The discharge end of the nozzle I is flanged at III, the discharge side of the flange Ill being tapered outwardly. The inner wall of the tubular membe 4 surrounding the valve seat 6, immediately adjacent the tapered surface of the flange ID, is cylindrical and is of slightly larger diameter than the valve disc I. A plurality of toothlike projections I I are positioned about the center of the tapered surface of the flange I0, adjacent the inner wall of the tubular member 4.

The position of the valve disc I with respect to the valve seat 6 determines the pattern of the spray discharged from the nozzle I. When the Valve disc 'I is in close proximity to the valve seat 6 the water or other fluid passing thru the orifice 5 is directed outwardly, at right angles to the axis of the nozzle I, and then changes its direction and forms a circular pattern as it passes thru the annular space between the edge of the valve disc 1 and the inner wall of the tubular membe 4. In this position the nozzle I is adapted to throw the water or other fluid the greatest distance forward. When the valve disc 1 is moved away from the valve seat 6 until it passes beyond the tapered surface of the flange It the Water or other fluid is thrown laterally as Well as forward and forms a conical pattern. The tooth-like projections H act as baiiies and tend to disperse the stream discharged from the nozzle I to form finely divided particles.

An annular groove I2 is formed about the periphery of the flange Ill. The groove standard equipment in nozzles of this type, and

ordinarily is provided for use in conjunctionwith an annular member which is. made of resilient material and acts as a cushion for the discharge end of the nozzle I, the annular member being receivable in the groove [2. In the device of this invention the annular groove I2 is usedto retain the foam generating attachment 2 in association with the fog nozzle I, as hereinafter described.

The foam generating attachment 2- includes a cylindrical barrel it which is of slightly larger diameter than the flange l and is-secured at one end to the flange NJ, as hereinafter described. The-wall of the barrel l3 is built up adjacent one end thereof, as indicated by the numeral I l, and an external-shoulder lfi-is adapted to engage one sideof an annular member [6 which surrounds the end of the barrel l3 adjacent the built up portion 14. A plurality of slots I! are formed in the built up portion M, the slots ll extending thru the wall of the barrel [3. A plurality of locking members l-8 are pivotally secured to pins t9 positioned in depressions formed inoneside'ofthe annular member l6. The depressions 20 are aligned with the slots 11-, and the locking members tB-are disposed partly in the depressions 20 andpartly in the slots ll. The slots I! are wider adjacent the outer wall of the built up portion I4 than they are adjacent the inner wall of the built up portion I l, and. the arrangement is such that when the annular member i6 is rotated with respect to the built up portion M- the locking members it are brought into engagement with the annular groove" [2, thereby securing thebarrel i3- to the flange H). A cover plate 2 i is-secured to the end of the built up portion M. The cover plate 21 retains the annular member I6 and the locking members t8 in engagement with the built up portion M. The numerals 22 indicate the positions of screws whichare used to secure the cover plate 2l to the built up portion 14.

An internal shoulder 23 is formed on the built up portion l4 and serves as a bearing for the flange HE. A resilient sealing ring 24 is positionedin an annular. groove 25 formed in the built up portion l4 adjacent the internal shoulder 23. The lockingmembers [8' are beveled at the point where they engage the annular groove l2, whereby the fiange I0 is urged against the sealing ring 24' as the locking members lfi'engage the annular groove l2.

A plurality of air ports 26 are formed in the wallofthe barrel I3 adjacent the inlet end' there of. The ports 26 are covered by baffles 21 which are attached. to the inner wall of the barrel. I3- on' the side of the ports 25 nearest the inlet end of the. barrel !3 and. are inclined inwardly from the wall of the barrel l3.

The foam generating attachment 2 is adapted I2 is" to receive a fluid spray, such as a mixture of water and foam producing liquid, as it is discharged from the nozzle l. Air is drawn into the barrel l3, thru the ports 26, and commingled with the liquid mixture by action of the vacuum created by the fluids passing thru the barrel [3. The baffles 21 tend to disperse the liquid mixture to form finely divided particles and aid in mixing the'liquid mixture with air drawn thru' the ports 2 6', as well as preventing the liquid mixture from being discharged thru the ports 26. The mass of foam so generated is shaped to form a circular pattern as it passes thru the remaining length of the barrel it; which gives a forward direction to the stream of foam as it is discharged from the device. The distance which the foam may be thrown, as it is discharged from the barrel i3 may be increased by bringing the valve disc 1 into closer proximity to the valve seat 6. The volume of foam produced may be increased by moving the valve disc I away from the valve seat t, which increases the mixing efiect and causes more air to be commingled with the liquid mixture.

The invention may be modified in various ways without departing from the spirit and scope thereof.

1- claim:

1. A foam generating attachment for fog nozzles comprising a cylindrical barrel having a plurality of ports formed in the wall thereof, each of the ports being at least partly covered-by an internal baffle, the baflles being attached to the inner wall of the barrel on one side of the ports and being inclined inwardly from the wall of the barrel, and means for securing one end of the barrel to the discharge end of a fog nozzle.

2. In combination with a fog nozzle, a foam generating attachment comprising a cylindrical barrel having one end thereof attached to the discharge end of the nozzle; the barrel having a plurality of ports formed in the wall thereof adjacent its inlet end, each of the ports being at least partly covered. by an internal: baffle, the bailles being attached to the inner wall of the barrel on the side of the ports nearest the inlet end of the barrel and'being inclined inwardly from the wall of the barrel. 7

3. In combination with a fog nozzle having: a

vflanged discharge: end, a foam. generating at tachment comprising a cylindrical barrel-having one-endthereof attached to the flangedv discharge: end of the nozzle, the barrel havinga plurality ofports formed in the wall thereof adjacent; itsinlet end, each of the ports being at least partly covered by an internal b'aiiie', the baffles being attached to the inner wall of the barrel on. the

side of. the ports nearest theinlet end' of: the

barrel and being inclined inwardly from the wall of thebarrel.

4-. Incombination with. a fog nozzle having a flanged discharge end, an annular groove being: formed about the periphery of the flanged discharge end, a foam generating attachment. com-- prising a cylindrical barrel. having a plurality of ports formed in the wall: thereof, each oftheportsv being at least partly covered by an internalbafiie; the baffies being attached to: the inner wall of the barrel on one side of the ports and beingv inclined inwardly. from the wall of: the barrel, and

means for securing one end of the-barrelto theflanged: discharge end of the nozzle comprising an annular member surrounding one end of the barrel, a plurality of slots being formed: in the end of the barrel and a. plurality of depressions being formed in one side of the annular member, and a plurality of locking members pivotally secured to pins positioned in the depressions, the slots being aligned with the depressions and the locking members being disposed partly in the depressions and partly in the slots, the arrangement being such that when the annular member is rotated with respect to the barrel the locking members are brought into engagement with the annular groove.

5. In combination with a fog nozzle, a foam generating attachment comprising a cylindrical barrel having one end thereof detachably secured. to the discharge end of the nozzle and adapted to receive the efiiuent therefrom, the barrel being aligned longitudinally with the nozzle and having a plurality of ports spaced about the circumference thereof adjacent its inlet end, the ports being positioned a short distance from the discharge end of the nozzle and in the path of the eflluent therefrom, each of the ports being at least partly covered by an internal baffle, the baffles being attached to the inner wall of the barrel on the side of the ports nearest the inlet end of the barrel and being inclined inwardly from the wall of the barrel.

6. In combination with an adjustable fog nozzle adapted to project a liquid either in the form of a finely divided mist or as a straight stream, a foam generating attachment comprising a cylindrical barrel having one end thereof detachably secured to the discharge end of the nozzle and adapted to receive the effluent therefrom, the barrel being aligned longitudinally with the nozzle and having a plurality of ports spaced about the circumference thereof adjacent its inlet end, the ports being positioned a short distance from the discharge end of the nozzle and in the path of the diluent therefrom, each of the ports being at least partly covered by an internal baille, the baffles being attached to the inner wall of the barrel on the side of the ports nearest the inlet end of the barrel and being inclined inwardly from the wall of the barrel.

'7. In combination with a fog nozzle comprising a pair of concentric tubular members, each of the tubular members having an inlet end and a discharge end, the inlet end of one of the tubular members being internally threaded and the discharge end of the other tubular member being externally threaded for engagement with the first mentioned tubular member, a restricted orifice being formed in the discharge end of the first mentioned tubular member and a valve seat being formed on the discharge side of the orifice, a valve stem disposed concentrically with respect to the tubular members and extending thru the orifice, one end of the valve stem being threaded for engagement with a spider carried by the last mentioned tubular member, and a valve disc secured to the other end of the valve stem for engagement with the valve seat, the discharge end of the first mentioned tubular member being flanged, the discharge side of the flange being tapered outwardly and the inner wall of the tubular member surrounding the valve seat, adjacent the tapered surface of the flange, being cylindrical, a foam generating attachment comprising a cylindrical barrel having one end thereof detachably secured to the flanged discharge end of the nozzle and adapted to receive the eifiuent therefrom, the barrel being aligned longitudinally with the nozzle and having a plurality of ports spaced about the circumference thereof adjacent its inlet end, the ports being positioned a short distance from the discharge end of the nozzle and in the path of the eilluent therefrom, each of the ports being at least partly covered by an internal baflie, the bafiles being attached to the inner wall of the barrel on the side of the ports nearest the inlet end of the barrel and being inclined inwardly from the wall of the barrel.

8. In combination with a fog nozzle having a flanged discharge end, an annular groove being formed about the periphery of the flanged discharge end, a foam generating attachment comprising a cylindrical barrel having one end thereof detachably secured to the discharge end of the nozzle and adapted to receive the eilluent therefrom, the barrel being aligned longitudinally with the nozzle and having a plurality of ports spaced about the circumference thereof adjacent its inlet end, the ports being positioned a short distance from the discharge end of the nozzle and in the path of the effluent therefrom, each of the ports being at least partly covered by an internal baffle, the baiiies being attached to the inner wall of the barrel on the side of the ports nearest the inlet end of the barrel and being inclined inwardly from the wall of the barrel, the barrel being detachably secured to the flanged discharge end of the nozzle by connecting means comprising an annular member surrounding the end of the barrel, a plurality of slots being formed in the end of the barrel and a plurality of depressions being formed in one side of the annular member, and a plurality of locking members pivotally secured to pins positioned in the depressions, the slots being aligned with the depressions and the locking members being disposed partly in the depressions and partly in the slots, the arrangement being such that when the annular member is rotated with respect to the barrel the locking members are brought into engagement with the annular groove.

DANIEL M. BUTLER.

REFERENCES CITED UNITED STATES PATENTS Number Name Date Friedrich Aug. 10, 193"! 

